Conversion from persistent to paroxysmal atrial fibrillation after pulmonary vein isolation is a good sign.

Although it is relatively rare, there are some patients with persistent or longstanding (LS) persistent atrial fibrillation (AF) who develop recurrences of AF with a paroxysmal form after pulmonary vein (PV) isolation [1]. Since there is no consensus on how to treat those patients, we tested what the results would be if they underwent a repeat ablation procedure. Consecutive patients were eligible for inclusion if they had any symptoms resulting from recurrent paroxysmal or persistent AF after PV isolation for the initial treatment of persistent or LS persistent AF, and then underwent a second ablation procedure. The types of AF were defined according to the current guidelines [2]. Written informed consent was obtained from all patients, and the study protocol was approved by the research committee of the institution. A double lasso guided extensive PV isolation with a cavotricuspid isthmus (CTI) ablation was performed in each patient as an initial ablation procedure. The details of the procedurewere described in our previous work [3]. In the second procedure, if any electrical reconnection was seen in the PVs or CTI, re-ablation was carried out in the samemanner as in the initial session. In principle, a roof line and anterior line [2] were additionally created if the patients had one or no reconnected PV. Finally, the superior vena cava was isolated circumferentially in all patients. The antiarrhythmic drugs withdrawn before the ablation were resumed the evening of the procedure in all patients. We scheduled to follow them up 3, 9, 12, and finally 24 months after the procedure to screen for any AF recurrences defined based on the current guidelines [2]. The end point was an AF recurrence occurring after the 2nd session in patients with a paroxysmal form of AF recurrence and those with a persistent form of AF recurrence after the 1st session.